Self-organized criticality with random toppling rules
Avalanche size: — | Total grains: —
The Manna model is a stochastic sandpile: when a site has ≥2 grains, it topples by sending two grains to random neighbors (not deterministic like BTW). This universality class gives exponent τ≈1.27. Color: blue=0, green=1, orange=active toppling. Histogram shows avalanche size distribution approaching a power law at criticality.